Behavior develops from a variety of factors interacting across domains and time scales. To capture the richness of behavioral development and to understand its complexity, most developmental scientists record behavior on video. The average developmental science laboratory collects 12 hours of video per week. However, researchers rarely share video data, and this has slowed progress, impeded understanding, and diminished the impact of public investments in behavioral science. The Databrary project aims to increase scientific transparency and accelerate discovery in developmental science by building the culture and infrastructure for developmental researchers to share video data. The project has five aims: (1) Transform the culture of developmental science by building a community of researchers committed to open video data sharing; (2) Expand the free, open source video coding software, OpenSHAPA, to enable coding, exploring, and analyzing video; (3) Build a data management system to support data sharing within laboratories, among collaborators, and in the Databrary repository; (4) Create participant permissions and contributor/user standards that enable open sharing of video data while limiting access to authorized users and ensure participant confidentiality; (5) Create a web-based Databrary repository for open sharing and preservation of video data. The overall innovation of the project is the emphasis on open sharing of video data. The Databrary will be the first large-scale repository for sharing video data and related information. A second important innovation is the emphasis on community building and on transforming the culture in developmental science. The contribution of a particular dataset will no longer depend on the private activities of researchers from one laboratory, but instead benefit from the critique and imagination of many researchers with different viewpoints. Databrary users will be able to view one another's datasets thereby promoting greater transparency and peer oversight and supporting inquiry into data collection methods and measurement. Users will be able to reanalyze shared videos to test competing hypotheses, perform integrative analyses, learn from prior examples, and address new questions beyond the scope of the original study-enabling new possibilities for research in laboratories with limited financial and technical resources. By creating the tools and infrastructure for open video data sharing, we expect to deepen insights in developmental science. Moreover, the Databrary tools and infrastructure will enhance data sharing and management in the entire behavioral science community.